ADS953 Datasheet, PDF (1/6 Pages) List of Unclassifed Manufacturers – 18-Bit, 1MHz, Low-Distortion Sampling A/D Converters

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ADS-953
18-Bit, 1MHz, Low-Distortion
Sampling A/D Converters
FEATURES
• 18-bit resolution
• 1MHz minimum sampling rate
• No missing codes over extended temperature range
• Very low power, 1.45 Watts
• Small, 32-pin, side-brazed, ceramic TDIP
• Edge-triggered
• Excellent performance, –95dB peak harmonics
• Ideal for both time and frequency-domain applications
• Low cost
GENERAL DESCRIPTION
The ADS-953 is an 18-bit, 1MHz sampling A/D converter. This
device accurately samples full-scale input signals up to Nyquist
frequencies with no missing codes. This feature, combined with
excellent signal-to-noise ratio (SNR) and –95dB peak harmonic
distortion (THD), makes the ADS-953 the ideal choice for both
time-domain (medical imaging, scanners, process control) and
frequency-domain (radar, telecommunications, spectrum analy-
sis) applications.
Packaged in a 32-pin, side-brazed, metal-sealed, ceramic TDIP,
the functionally complete ADS-953 contains a fast-settling sam-
ple-hold amplifier, a subranging (two-pass) A/D converter, an
internal reference, timing/control logic, and error-correction cir-
cuitry. Digital input and output levels are TTL, and the ADS-953
only requires the rising edge of the start convert pulse to
operate.
Requiring ±15V and ±5V supplies, the ADS-953 typically dis-
sipates 1.45 Watts. The device is offered with a bipolar (±5V)
analog input range. Models are available for use in either
commercial (0 to +70°C) or extended (–40 to +110°C) operat-
INPUT/OUTPUT CONNECTIONS
PIN FUNCTION
PIN FUNCTION
1 BIT 2
32 BIT 3
2 BIT 1 (MSB)
31 BIT 4
3 ANALOG GROUND
30 BIT 5
4 ANALOG INPUT
29 BIT 6
5 +5V REFERENCE OUT 28 BIT 7
6 GAIN ADJUST
27 BIT 8
7 COMPENSATION
26 BIT 9
8 –15V SUPPLY
25 BIT 10
9 +15V SUPPLY
24 BIT 11
10 +5V ANALOG SUPPLY 23 BIT 12
11 –5V ANALOG SUPPLY 22 BIT 13
12 ANALOG GROUND
21 BIT 14
13 DIGITAL GROUND
20 BIT 15
14 +5V DIGITAL SUPPLY 19 BIT 16
15 EOC
18 BIT 17
16 START CONVERT
17 BIT 18 (LSB)
ing temperature ranges. A proprietary, auto-calibrating, error-
correcting circuit enables the device to achieve specified per-
formance over the full military temperature range.
ANALOG INPUT 4
–
S/H
+
BUFFER
FLASH
ADC
1
GAIN ADJUST 6
+5V REFERENCE OUT 5
COMPENSATION 7
GAIN
CIRCUIT
REF
Σ
START CONVERT 16
EOC 15
AMP
TIMING AND
CONTROL LOGIC
DAC
FLASH
ADC
2
2 BIT 1 (MSB)
1 BIT 2
32 BIT 3
31 BIT 4
30 BIT 5
29 BIT 6
28 BIT 7
27 BIT 8
26 BIT 9
25 BIT 10
24 BIT 11
23 BIT 12
22 BIT 13
21 BIT 14
20 BIT 15
19 BIT 16
18 BIT 17
17 BIT 18 (LSB)
10
+5V ANALOG
SUPPLY
11
–5V ANALOG
SUPPLY
3, 12
ANALOG
GROUND
14
+5V DIGITAL
SUPPLY
9
+15V
SUPPLY
8
–15V
SUPPLY
Figure 1. ADS-953 Functional Block Diagram
13
DIGITAL
GROUND
DATEL, Inc., Mansfield, MA 02048 (USA) • Tel: [phone] Fax: [phone] • Email: [e-mail] • Internet: www.datel.com